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Does join order matter? 🤔
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From Excel to SQL
Everything about joins
Challenging SQL problems
SQL Learning Materials
GitHub
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From Excel to SQL
From Excel to SQL
From Excel to SQL
Getting Started
Getting Started
Setting the context 🤔
SQL syntax 📚
Main Concepts
Main Concepts
Gimme data 📁
Filtering 🚦
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TOP and DISTINCT 🔝
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Date formatting 📆
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Joins 🔗
Unions 🧬
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Window functions 📈
Logical processing order 🎥
Style guide ✨
Advanced Concepts
Advanced Concepts
Advanced aggregations 🥇
Correlated subqueries 🌐
Recursive CTEs 🔁
Everything about joins
Everything about joins
Everything about joins
Syntax
Syntax
Join fundamentals 🧩
More fundamentals 📚
The "timestamp" join (ASOF) ⏱
The "filtering" joins (SEMI, ANTI) 🚦
The "glue" join (POSITIONAL) 📎
The "explosive" joins (LATERAL) 💥
SQL-92 (ANSI-SQL join syntax) 📝
Under the hood
Under the hood
Joins with an index 🔍
Does join order matter? 🤔
Loop joins 🔄
Hash joins 🔑
Merge joins 🔀
Range intersection joins 🎯
Challenging SQL problems
Challenging SQL problems
Challenging SQL problems
Problems
Problems
🟤 Bronze Tier
🟤 Bronze Tier
Temperature anomaly detection 🔍
Outstanding invoices 💱
Personalised customer emails 📨
Suspicious login activity 🤔
Combining dimensions 🔗
Customer churn 🔄
Fibonacci sequence 🔢
UK bank holidays 📅
⚪ Silver Tier
⚪ Silver Tier
Metric correlation 🔀
Funnel analytics ⏬
Bannable login activity ❌
Bus routes 🚌
Decoding datelist ints 🔓
Region precipitation ☔
Predicting values 🎱
Mandelbrot set 🌀
Customer sales running totals 📈
🟡 Gold Tier
🟡 Gold Tier
Loan repayment schedule 💰
Risk invasions 🛡️
Supply chain network 🚛
Encoding datelist ints 🔐
Travel plans 🚂
Solutions
Solutions
🟤 Bronze Tier
🟤 Bronze Tier
Temperature anomaly detection 🔍
Outstanding invoices 💱
Personalised customer emails 📨
Suspicious login activity 🤔
Combining dimensions 🔗
Customer churn 🔄
Fibonacci sequence 🔢
UK bank holidays 📅
⚪ Silver Tier
⚪ Silver Tier
Metric correlation 🔀
Funnel analytics ⏬
Bannable login activity ❌
Bus routes 🚌
Decoding datelist ints 🔓
Region precipitation ☔
Predicting values 🎱
Mandelbrot set 🌀
Customer sales running totals 📈
🟡 Gold Tier
🟡 Gold Tier
Loan repayment schedule 💰
Risk invasions 🛡️
Supply chain network 🚛
Encoding datelist ints 🔐
Travel plans 🚂
Questions by topic
Does join order matter? 🤔
Success
We can join tables in any order...
ANSI vs non-ANSI joins